Mold-specific IgE antibodies in relation to exposure and skin test data in schoolchildren

Background: The purpose of the present study was to compare mold specific IgE results with skin test and exposure data, as well as in relation to asthma and other allergic manifestations. Methods: We performed skin prick tests (SPT) to 13 molds in 341 children from six schools and studied the microbial status of all school buildings. Subsequently, mold specific IgE was measured by enzyme immunoassay (EIA) to 10 molds in 31 of those children with a positive (≥3 mm) or weak SPT reaction (1–2 mm) and in 62 age- and sex-matched controls with no such reactions. Results: Mold-specific IgE was elevated by EIA (>0.35 lU/mL) to at least one of the 10 studied species in 12 children (39%) with and in two children (3%) without skin test reactions. The calculated prevalence of elevated mold-specific IgE was 5% in the non-selected and 10% in children selected by respiratory morbidity. Six children had IgE to the dampness-indicative mold Aspergillus fumigatus, five children had IgE to the common outdoor mold Cladosporium herbarum and four children had IgE to the uncommon, but highly allergenic, indoor mold Rhizopus nigricans. All 14 children who had elevated IgE to molds were boys, 13 had atopy by skin tests and 12 had either asthma or had wheezed. However, no species-specific association was found between IgE or SPT responses and exposure to molds. Conclusions: Mold allergy, as assessed by IgE measurements or skin tests, is rare in children. School- aged asthmatic boys having exposed to indoor air dampness seem to form a susceptible group for mold allergy, being at risk for worsening of their asthma.